Next-Gen DNA Sequencing Illuminates Mutations in Lung Cancer

Wed, 12/16/2009 - 17:08 — bioquicknews

Aided by powerful next-generation DNA sequencing technology, researchers have identified nearly 23,000 mutations in a patient’s small cell lung cancer. The mutations were identified by comparing the entire genetic sequence of the cancer against that of normal DNA from the same patient. In the process, the researchers also identified a new gene (CHD7) associated with lung cancer. The number of mutations found in the study suggests that a person may develop one mutation for every 15 cigarettes smoked, said Dr. John Minna, director of the Nancy B. and Jake L. Hamon Center for Therapeutic Oncology Research at the University of Texas Southwestern and one of the authors of the new study. The researchers said the findings illustrate the power of advanced technology to provide important new information about human cancer, including the effect of cancer-causing chemicals on the body and the identification of potential new therapeutic targets. "Cancer is driven by acquired mutations in genes, and we are at a point where it soon will be possible to actually know every mutation in the tumors of each of our patients," Dr. Minna said. "The key will be to use this information to find new ways to help prevent cancers, diagnose them earlier, and to select treatments that might be specific for each patient's tumor. While these findings are the first step, they have lighted our path to clearly point us in the right direction. In addition, they provide the first detailed analysis of a human cance–lung cancer–that is closely linked to smoking." Furthermore, Dr. Minna said, "The data demonstrate the power of whole-genome sequencing to untangle the complex mutational signatures found in cancers induced by cigarette smoke. In addition, the protein product of the CHD7 gene now becomes a new marker for early diagnosis and also for potentially targeted therapy." The authors believe that their findings illustrate the potential for next-generation sequencing to provide unprecedented insights into mutational processes, cellular repair pathways, and gene networks associated with cancer. This work was published online in Nature on December 16. [Press release] [Nature abstract]